1. Technical Field
The present invention relates generally to sewing machinery, and more specifically, to an overlock sewing machine and flanger system especially for use in processing heavy duty fabrics, textile materials and the like, such as material or fabric panels for use in mattress construction.
2. Description of Related Art
When preparing and quilting panels for use as, e.g., top and bottom cover panels in mattresses, the panels are generally initially cut with spare material in both the length and width dimensions. This is due to the fact that the next operation after cutting the cover panel (which leaves raw edges on all four sides) is to sew and close the panel, e.g., with an overlock sewing machine.
While it is desirable to leave a consistent overcut (e.g., typically about 1.0 inch to about 3.0 inches of extra material overhanging each edge of the panel), quilting operators often set up panel cutters inconsistently, leaving more or less than the desired material overcut on the length and width dimensions of each panel. In addition to this problem, manual sewing operators often trim panels inconsistently, either trimming too much or not enough material. Further, the panels, once trimmed in their length and width dimensions, undergo some amount of shrinkage due to tension applied in the sewing pattern, thus affecting their actual overall length and width dimensions, often by an inch or more.
Moreover, when processing (trimming/sewing) the corners of a panel (preferably to achieve rounded corners), sewing operators often have great difficulty in producing consistent results in accordance with factory-specified corner radius specifications. For example, due to material handling issues and/or human inconsistency, operators of serger/flanger machines often will, e.g., begin the corner turn too early/too late, and/or not turn the panel smoothly and consistently during the pivot, resulting in a less than the optimal (e.g., 90 degree) arc. As such, a number of defective panels are inevitably produced and wasted.
Typically, in fully automated machinery, processes are performed by the machine to adhere to specific guidelines and are carried out in accordance with specific protocol at definite times. Consequently, the processes are often forced and a human operator has little or no control or input during, e.g., manipulation and sewing of a product. Machines that strictly dictate the procedures that must be done and how quickly the operator must perform the task, invoke a disconnected and forced work atmosphere, causing stress to human operators and ultimately reducing finish quality of the product. Bulky materials, such as, e.g., mattress panels, often require fine-tuning in their positioning and orientation during processes such as trimming and sewing. Such fine-tuning must also be performed in real-time and is difficult, if not impossible to achieve satisfactorily via machinery alone.
Accordingly, an efficient and effective system and method for accurately producing consistently sized and shaped mattress cover panels according to desired dimensions while incorporating user input in real-time is highly desirable.